Apparatus for the detection of broken yarn and the like on textile machines



Aprll 11, 1967 A. H. ARCHER 3,313,192

APPARATUS FOR THE DETECTION OF BROKEN YARN AND THE LIKE ON TEXTILE MACHINES Filed July 19, 1965 2 Sheets-Sheet 1 INVENTOR ANTHONY HUGH 4/90/52 ATTORNEYS P 11, 1967 A. H. ARCHER 3,313,192

APPARATUS FOR THE DET ECTION OF BROKEN YARN AND THE LIKE ON TEXTILE MACHINES Filed July 19, 1965 2 Sheets-Sheet 2 fiwzeui/ve, 6950?, Qaeg ff/FAW ATTORNEYS United States Patent Ofilice 3,313,192 Patented Apr. 11, 1967 3,313,192 APPARATUS FGR THE DETECTION F BROKEN YARN AND THE LIKE 0N TEXTHLE MACHINES Anthony Hugh Archer, 32 Homeiield, Road, 01d Coulsdon, England Filed July 19, 1965, Ser. No. 473,094 Claims priority, application Great Britain, July 17, 1964, 29,347/64 7 Claims. (Cl. 83-370) The present invention is a continuation-in-part of copending application Ser. No. 387,634, now Patent No. 3,272,048.

This invention relates to apparatus for the detection of breaks in textile material such as yarns, rovings and slivers, in textile machines, and is particularly applicable to multi-spindle spinning machines. The invention will be described by way of example only with particular refference to a ring spinning machine, but it will be appreciated that the invention is applicable to any type of textile machine or machinery where it is required to detect the existence of a break in the textile material in order that suitable action may be taken to avoid wastage of the textile material and/ or damage occurring to the textile material and/ or machinery.

In continuous spinning machines, the textile material is delivered, twisted and wound on to a package or spindle, simultaneously and without interruption. An example of such a machine is a ring spinning machine in which the bobbins of roving are positioned in a creel on the upper part of the framework of the machine. The roving from each bobbin is fed to the drafting rollers of a drafting unit, and Wound on to a spindle which rotates at a speed usually between 5000 and 10,000 revolutions per minute. Located around each spindle is a ring having a traveller which is arranged to move around the ring. The ring and traveller are traversed in relation to the spindle, to build a package on the spindle.

The yarn issuing from the drafting rollers is threaded through a small ring-shaped yarn guide known in the art as a ballooning eye, twizzle guide, pigtail, lappet or thread guide and will be hereinafter referred to as the yarn guide. The yarn guide is located vertically above the spindle and the yarn is passed through the yarn guide, through the traveller and thence on the spindle.

A feature of ring spinning is that a balloon of yarn is formed intermediate the yarn guide, which forms the apex of the yarn balloon, and the traveller. The balloon is the shape formed by the yarn path in this region during spinning and the shape of the balloon is determined by the air resistance in passing the yarn around the spindle, the centrifugal force exerted in the revolving yarn, the count and type of yarn, the yarn winding speed and other factors.

It has been found that due to the twisting and rotation of the yarn, the balloon vibrates at the frequency of rotation of the spindle and in the vicinity of the yarn guide, these vibrations are transmitted thereto as long as the yarn remains unbroken.

In the present invention use is made of this phenomena to provide an indication of the occurrence of a break in the textile material.

It is an object of the present invention to provide apparatus for the detection of breaks in textile material without adding to the strain imposed on the material in process.

A further object of the present invention is to provide means for the detection of breaks in textile material and arranged upon the occurrence of a break, to actuate means, such as warning apparatus, machine stop motions, feed interrupting means and the like.

Thus, according to one feature of the present invention there is provided apparatus for detecting the existence of a break in textile material passing through a textile machine, comprising transducing means responsive to vibrations imparted to the material by an operation performed thereon during passage thereof through the machine to produce electrical signals in response to said vibrations and means responsive to the absence of, or interruption of said vibrations and signals to provide an indication of the existence of a break in the material.

According to one specific embodiment of the present invention there is provided apparatus for detection of a broken yarn in a ring spinning machine in which a roving is passed through drafting rollers and via a yarn guide to a spindle on which the yarn is wound, comprising a transducing head responsive to vibrations imparted by the yarn balloon to the yarn guide such as to produce electrical output signals continuously from said transducing head whilst the yarn is unbroken, and means responsive to any interruption of the electrical output signals for operating warning devices, feed interrupting devices or stop motions.

A feature of the present invention is that use is made of the existing components of textile machines and no additional means is introduced into the path of the textile material. Thus, no additional wear or strain is imposed on the material as it passes through the machine.

It will be appreciated that in order to operate efficiently and effectively, the detector device should respond only to the vibrations imparted to the material by an operation performed thereon during the passage of the material through the machine, or in the case of a ring spinning machine, only to the vibrations imparted by the yarn balloon to the yarn guide or lappet, and that all extraneous vibra tions should be inhibited or at least reduced to a minimum.

It is thus a further object of the invention to provide a broken textile material detector device wherein extraneous vibrations are damped or reduced to a minimum.

Thus, according to a further feature of the invention, there is provided a selector device of the kind described above wherein means are provided to allow the vibrations imparted by the material to be passed to the transducer means and to reduce to a minimum the passage of vibrations from all other sources.

In the application of the invention to ring spinning machines, the yarn guide or lappet is resiliently mounted on the frame of the machine such that the machine vibrations are damped or filtered but allowing the vibrations imparted to the yarn guide or lappet of the machine to be conveyed to the transducer to produce output signals therefrom in response to the vibrations imparted to the yarn guide only.

The invention will now be described by way of example only with particular reference to the accompanying drawings wherein FIGURE 1 is a side elevational view of the drafting unit, lappet and spindle of a ring spinning machine, FIGURES 2 and 3 are side and end elevational views of the detector means of FIGURE 1, showing the detector means in greater detail, and FIGURE 4 is a sectional view of the detector head of the present invention.

Although the invention will be described with reference to a ring spinning machine, it will be appreciated that, as previously stated, the detector means according to the present invention may be used in any textile machine where the material has vibrations imparted thereto by any operation performed thereon during passage of the material through the machine, and where such vibrations are of sufficient magnitude to produce detectable electrical signals from the output of a transducer.

Referring to FIGURES 1-3, and more particularly to 3 FIGURE 1 of the drawings, the yarn 1 is passed by drafting unit 2 and drafting rollers 3, 4, through yarn guide or lappet 5, to traveller 6 for winding on bobbin 7. The path traced out by the yarn, i.e., the balloon is shown by the full and chain-dot lines 1, 1" in FIGURE 1.

The vibrations of the yarn in the region of the yarn guide are imparted thereto and transmitted to a transducer 8 which preferably comprises an extremely sensitive multi-electrode piezo-electric crystal mounted in the detector head 9, which, as shown in FIGURE 1, is arranged in the vicinity of the yarn guide 5 so as to respond to vibrations imparted to the yarn at this point and to produce electrical output signals continuously therefrom whilst the yarn is passing through the yarn guide.

It is clear that the detector device should operate to detect the absence of yarn, i.e., the existence of a broken yarn and because of the fragility of the yarn, no contact should be made by the detector, with the yarn to avoid breakage thereof.

To meet the above requirements, the yarn guides of existing spinning machines may be modified by providing a suitably mounted arm 10 formed integrally with the yarn guide 5 and responsive to the vibrations imparted thereto, such as to transmit such vibrations to the crystal 8. The constructional features of a transducing head will now be described with particular reference to FIGURE 4.

The arm 10 formed integrally with the yarn guide or lappet 5 is resiliently mounted on a supporting plate 11 provided with clips or the like 12 for mounting the detector head 9 on a rail 13 of the machine.

The supporting arm 10 passes through a resilient bush 14 of rubber or plastics material, located Within a rigid sleeve 15 secured to, and projecting from, the supporting plate 11.

The supporting arm 10 passes through the bush 14 in the sleeve 15 and projects beyond the plate 11 on the side remote from the yarn guide or lappet 5. The extension 10a of the supporting arm 10 is provided with a collar 16 secured thereon and supporting a link 17 connected to one side of the crystal 8. The collar 16 and link 17 move in unison with the lappet supporting arm 10 but rotational movement of the latter is restricted by means of a pin 18 passing through a transverse bore 19 formed in the sleeve 15, bush 14 and supporting arm 10.

The construction is such that any vibrations imparted by the yarn balloon to the yarn guide or lappet 5 are transmitted via the supporting arm 10, collar 16 and link 17 to the crystal 8 to produce electrical signals therefrom in response to the mechanical stress applied thereto.

Any machine vibrations or other extraneous vibrations will be damped or filtered by the resilient bush 14 allowing only the yarn vibrations to pass to the crystal 8. If necessary means may be provided to damp or reduce some of the vibrations transmitted to the crystal 8.

The electrical output signals from the crystal are passed to an amplifier which may be of conventional form and preferably transistorised and the amplified signals applied to the coil of a relay, to effect energisation thereof such that the contacts thereof are normally open.

In a spinning machine, the spindles may be arranged in banks of fifty and each spindle would have associated therewith a separate detector head sensitive to the vibration of the spinning yarn being wound on the respective spindle; the frequency being determined by the speed of rotation of the spindle which is normally rotating at approximately 7000 rpm. However, it is not necessary to provide a separate amplifier for each detector head.

According to a preferred embodiment of the invention, a scanning device such as a uniselector is used to scan a bank of 50 or 100 detector heads within a predetermined time interval, e.g., 10 seconds. Should it be necessary to reduce the natural speed of scan of the wiper of the uniselector from, e.g., l revolution per second, to, e.g., 1 revolution every 10 seconds, it would be necessary to provide a delay-type relay.

The outputs from the detector heads would be connected to a respective one of the contacts of the uniselector connected to the input of the amplifier unit. Thus as the wiper of the uniselector traverses a bank of contacts, current impulses will be passed to the input of the amplifier unit and the amplified signals passed to the coil of the output relay, to effect energisation thereof and retain the associated relay contacts in the normally-open position. These contacts are connected in circuit with a plurality of cutter units corresponding in number to the number of detector heads. Each cutter comprises a solenoid connected to the respective output of the uniselector and arranged when energized to operate a cutting device located at a predetermined point, preferably immediately prior to the back rollers of the drafting system. Thus, when a break occurs in the yarn of any unit of a bank, the output signals from the respective detector head are interrupted and as the wiper of the uniselector traverses its bank of contacts, the input to the amplifier will be interrupted when the Wiper is in contact with the contact of the uniselector corresponding to the detector head from which the output signals have been interrupted. The normally energised relay located in the output of the amplifier unit will be de-energised and cause the associated contacts to close, complete a circuit to the respective cutter solenoid, to effect energisation thereof and consequent actuation of the cutter to cut the yarn behind the back rollers of the drafting system.

If necessary, two uniselectors maybe employed to scan two 50 bank units in unison. In such an arrangement, the output signals from the detector units are fed to respective contacts of one or other of the uniselectors and a single amplifier unit coupled to the outputs of both uniselectors. Similarly, the cutter unit solenoids are connected to a respective one of the uniselector contacts via the normally-open contacts of the output relay of the amplifier unit.

It will be seen from the above description that since the individual detector heads are each responsive to the vibrations of the yarn passing through the respective yarn guide, any broken yarn will immediately be detected by the absence of vibrations and the interruption of the output signals from the respective detector head. As soon as the scanning device detects the particular unit of a bank in which a yarn has broken, the cutting device of that unit is operated to cut the roving, thereby re ducing the possibility of damage occurring to the roving on adjacent spindles, to a minimum and enabling an operator to rejoin the yarn with the minimum possible delay and efifort.

If necessary, the output relay from the amplifier unit may have further contacts associated with an audible or visual warning device, such as to provide an immediate indication to the operator, of the existence of a broken yarn in any unit of a bank.

It will be appreciated that although the invention has been described in connection with the operation of yarn cutters following the detection of a broken yarn, the invention is equally applicable to textile machines where no cutting operation is necessary and to machines where the broken material may be automatically joined in response to an indication of the existence of a break in the material.

I claim:

1. A yarn spinning apparatus comprising a yarn drafting means, a yarn guide, a stationary member having means for winding yarn about a bobbin, and means for holding a bobbin;

said drafting means being adapted to feed yarn towards said yarn guide and said winding means;

said yarn guide being adapted to engage the yarn between said drafting means and said winding means; the operation of said winding means vibrating said yarn guide by vibrating the yarn in engagement therewith;

a stationary apparatus member;

resilient mounting means supporting said yarn guide from said stationary apparatus member;

a detector device for detecting a break in the yarn connected to said yarn guide so as to be preferentially responsive to the presence of vibrations in said yarn guide and minimally responsive to other vibrations;

said device being differently responsive to the absence of vibrations in said yarn guide due to a break in the yarn.

2. The apparatus of claim 1, in which a shaft means is connected to said yarn guide;

said resilient mounting means includes, a support member mounted on said stationary member, a rigid sleeve secured to said support member, a resilient bush within said sleeve, said shaft means passing through said bush.

3. The apparatus of claim 2, in which, a pin having a first diameter passes through said bush and transversely through said shaft means;

said bush being securely fitted within said sleeve; said bush fitting securely about said pin;

said pin extending outwardly from said bush and entering said sleeve; said sleeve having openings having a second diameter; said pin being aligned with said openings; said second diameter being greater than said first diameter,

whereby rotation of said shaft means is prevented while torsional vibration thereof is permitted.

4. The apparatus of claim 2 in which,

said detector device comprises said shaft means and a detector means;

said detector means being mounted on said support member;

said yarn guide being integral with said shaft means;

a portion of said shaft means protruding from said bush;

said detector device further comprising link means connecting said protruding portion of said shaft with said detector means;

whereby vibration of said yarn guide activates said detector device.

5. The apparatus of claim 4, wherein said link means includes,

a collar embracing and secured to said protruding portion of said shaft,

and an arm secured to said collar and extending into contact with said detector means, thereby to actuate said detector upon vibration of said yarn guide.

6. The apparatus of claim 4 wherein said detector means comprises a multi-electrode piezo-electric crystal,

which is so positioned with respect to said link means as to be stressed through the intermediary of said link means.

7. A textile producing machine comprising, a plurality of yarn spinning apparati and a detector device for detecting a break in the yarn passing through any of the plurality of apparati;

each of said plurality of apparati comprising a yarn drafting means, a yarn guide having a support arm,

a means for winding yarn about a bobbin and means for holding a bobbin;

said drafting means being adapted to feed yarn towards said yarn guide and said winding means;

said yarn guide being adapted to engage the yarn be tween said drafting means and said winding means; the operation of said winding means vibrating said yarn guide by vibrating the yarn in engagement therewith;

said machine including a stationary apparatus member in the vicinity of each one of said apparati;

a support member mounted on each of said stationary apparatus members;

a like plurality of vibration transducers for changing vibration into electrical impulses, each being mounted on an individual one of said support members;

means mounting each said yarn guide support arm resiliently to a respective one of said support members;

and link means connecting each said support arm to the said vibration transducer mounted on the same support member as said arm;

whereby said vibration transducer is preferentially responsive to vibration of said support arm and is minimally responsive to other vibration in said machine;

said vibration transducer being differently responsive to the absence of vibrations in said yarn guide due to a break in the yarn.

References Cited by the Examiner UNITED STATES PATENTS 2,524,579 10/1950 Taylor 19.25 X 2,734,335 2/1956 Saunders et al 19.25 X 2,804,744 9/1957 Breuning 19.25 X

FOREIGN PATENTS 878,524 10/ 1961 Great Britain.

WILLIAM S. LAWSON, Primary Examiner. 

1. A YARN SPINNING APPARATUS COMPRISING A YARN DRAFTING MEANS, A YARN GUIDE, A STATIONARY MEMBER HAVING MEANS FOR WINDING YARN ABOUT A BOBBIN, AND MEANS FOR HOLDING A BOBBIN; SAID DRAFTING MEANS BEING ADAPTED TO FEED YARN TOWARDS SAID YARN GUIDE AND SAID WINDING MEANS; SAID YARN GUIDE BEING ADAPTED TO ENGAGE THE YARN BETWEEN SAID DRAFTING MEANS AND SAID WINDING MEANS; THE OPERATION OF SAID WINDING MEANS VIBRATING SAID YARN GUIDE BY VIBRATING THE YARN IN ENGAGEMENT THEREWITH; A STATIONARY APPARATUS MEMBER; 